When I woke up at night in my room at the Knight Academy, I heard a very unexpected sound coming from the room next door. Investigating, I found Fledge doing push-ups, trying to get stronger. I've helped him twice now, and he's still not satisfied. Will he ever succeed and show some gratitude for my help?

It's possible that the advancement is triggered by specific main quest progress, in which case you might not have to wait as long between steps if you're already far along - otherwise if you started the side quest when near the end of the game, it wouldn't be finishable! (But I'm not sure.)
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JefromiDec 26 '11 at 17:14

@Jefromi: In those circumstances, you just need to be at a certain point in the game. On my first playthrough of the game, I didn't realize he had multiple phases in his quest. I only gave him the first potion and always saw him in the day with the little quest icon over him in the day. Every time I spoke to him (when I first noticed it), he always said "thanks" but never seemed to say anything else so I ignored it until much much later. It was only when I reached the end of the game that I realized that I needed to give him another potion. After visiting the next night, I got the crystals.
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Jeff MercadoDec 26 '11 at 17:57